Clothes washer having an oscillating and spinning drive mechanism

ABSTRACT

In the preferred form, a drive mechanism for a washing machine having an integral spin tub and agitator, wherein a reversible motor is utilized to rotate a driven spin roller through a friction drive and to oscillate a slider crank drum through an improved slider crank drive, and wherein a clutch mechanism is utilized upon the direction of rotation of the reversible motor to selectively impart to the integral spin tub and agitator the oscillatory motion of the slider crank drum during a washing cycle and the rotary motion of the driven spin roller during a spin cycle.

United States Patent [72] Inventor Bryron L. Brucken Dayton, Ohio [211App]. No. 798,298 [22] Filed Feb.11,l969 [45] Patented June 15,1971 [73]Assignee General Motors Corporation Detroit, Mich.

[541 CLOTHES WASHER HAVING AN OSCILLATING AND SPINNING DRIVE MECHANISM 1Claim, 9 Drawing Figs.

[52] US. Cl 68/23 [51] Int. Cl D06f 23/04 [50] Field of Search ..68/23.23.3, 23.6, 23.7; 74/82 [56] References Cited UNITED STATES PATENTS1,696,718 12/1928 Kuhmann et al 68/237 i l i i t i g :6 g V i 2,634,6154/1953 74/82 2,810,295 10/1957 74/82 2,930,216 3/1960 68/23 X 3,087,3214/1963 Brucken 68/23.6

Prima'ry Examiner-William 1. Price Attorneys-Warren E. Finken andFrederick M. Ritchie PATENTEU JUN 1 5 I97! SHEET 3 BF 4 PATENTEI] JUN]519m SHEET 4 OF 4 agmm A T T02 NE Y CLOTHES WASHER HAVING AN OSCILLATINGAND SPINNING DRIVE MECHANISM This invention relates to a domesticappliance and, more particularly, to an improved oscillating andspinning drive mechanism for a clothes washer.

In the clothes washing art, agitating and spinning mechanisms havebecome quite complex requiring the utilization of many parts and in manycases requiring a bulky lubrication system. As the number of partsincrease, there is often a proportionate increase in weight, spacerequirements, and cost. It is, therefore, an object of this invention toprovide a simplified oscillating and spinning drive mechanism which willrequire fewer parts, eliminate the critical need for lubrication, andprovide a savings in cost, weight, and space requirements. In thewashing machine art, a reduction in weight and space requirementsprovides the potential of either an increase in load capacity ordecrease in unit size.

Accordingly, it is an object of this invention to provide an oscillatingand spinning drive mechanism for a washing apparatus of the dry-runningtype broadly taught in my U.S. Pat. No. 3,087,321, granted Apr. 30,1963.

In the washing machine art, by integrally molding an agitator with aspin tub it is possible to obtain an extremely lightweight unit in theorder of 4 pounds when empty. The resultant weight saving makes itpossible to consolidate the drives for agitate and spin. It is,therefore, an object of this invention to provide a simplifiedoscillating and spinning drive mechanism to selectively impart to anintegral agitator and spin tub an oscillatory agitating motionforwashing and a rotary motion for spin drying.

In keeping with the simplified oscillating and spinning drive mechanism,it is an object of this invention to provide a friction roller rotarydrive and an automatically adjusted slider crank oscillatory drive, bothof which drives can be imparted to a single output drive shaft.

Another object of this invention, is the provision of a simplifiedclutch mechanism which, dependent upon the direction of rotation of thereversible motor, selectively engages either the oscillatory drive orthe rotary drive to impart the selected motion to the tub drive shaft.

It is a further object of this invention to provide an im provedself-retracting roller in the friction roller rotary drive to decreasescuffu'ig wear during the washing cycle.

An advantage of this invention lies in the fact that manufacturingtolerances are less critical than those in other washing machine drivemechanisms.

Another advantage of this invention lies in the economy of designwherein fewer components are required which results in cost savings, aweight savings, and a space requirement savings.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings, wherein preferred embodiments of the present invention areclearly shown.

IN THE DRAWINGS:

FIG. 1 is a vertical elevation with parts broken away of a clotheswasher provided with the dry running oscillating and spinning drivemechanism of this invention.

FIG. 2 is a vertical elevation with parts broken away of the oscillatingand spinning drive mechanism.

FIG. 3 is a bottom plan view taken along line 3-3 of FIG. 2 to show theoscillating and spinning drive mechanism with the slider crank arm in aplurality of operating positions.

FIG. 4 is a fragmentary isometric view of the oscillating and spinningdrive mechanism of this invention.

FIG. 5 is a vertical sectional view of a clutch mechanism utilized inthe oscillating and spinning drive mechanism of this invention.

FIG. 6 is an exploded perspective view of the clutch members of theclutch mechanism with parts removed to show the clutch-actuating camsurfaces in the preferred form of the invention.

FIG. 7 is a sectional view of the intermediate pulley belttensioningdevice.

FIG. 8 is a bottom plan view of the slider crank and slider crank drumwith the clutch removed.

FIG. 9 is a sectional view of the roller retraction device shown in FIG.3.

GENERAL In accordance with this invention and with reference to FIG. I,a clothes washer 2 is shown having an outer tub or water container 4.The outer tub 4 is mounted on a suspension system having a support plate6 which :is located by a plurality of support braces 8 extendingupwardly from an upper convex plate 10. A lower convex plate 12 formspart of the clothes washer base. A snubber shuttle I4 is sandwichedbetween the upper convex plate 10 and the lower convex plate 12. Thesnubber shuttle 14 is free to move according to the forces applied bythe upper and lower convex plates. The upper convex plate 10, and,therefore, the support braces 8, support plate 6, and outer tub 4 arecentrally located with respect to the washing machine casing by aplurality of suspension springs 15. Frictional forces between the plates10 and I2 and the snubber shuttle 14 provide the dampening forces forthe suspension system. The springs 15 not only provide a centering biasfor the suspension system, but also provide a downward force which,along with the weight of the washing machine components and clothesload, help increase the dampening characteristics by increasing thefrictional forces between the snubber shuttle l4 and the plates 10 and12. My copending application Ser. No. 766,198, now US. Pat. No. 3,493,]18, granted Feb. 3, 1970, describes a suspension system of this type indetail.

Mounted within the outer tub 4 is an inner tub or spin tub 16. In thepreferred form of this invention, an agitator 18 is integrally moldedwith, and centrally located within, the spin tub 16. It is also withinthe purview of this invention to attach an independent agitator to thespin tub 16 to form a unitary structure. Either way, and consideringusing a plastic such as polypropylene as the material for molding, aweight savings is obtained.

Supported beneath the support plate is the oscillating and spinningdrive mechanism 20 of the clothes washer which is the subject of thisinvention. Extending upwardly from the oscillating and spinning drivemechanism 20 is the tub drive shaft 22. The tub drive shaft 22 extendsthrough the support plate 6 and the outer tub 4. The tub drive shaft 22is rotatably mounted with respect to the support plate 6 by a sleevebearing 23. Located on the upper end of the tub drive shaft 22 is a spintub support 24. As in the preferred form of this invention, the agitator18 is integrally molded with, and centrally located with respect to, thespin tub 16. The agitator portion i8 is slipped over the spin tubsupport 24 so as to provide a driving connection between the tub driveshaft 22 and the integral spin tub and agitator l6 and 18. This drivingconnection may thus be maintained by the weight of the spin tub l6 andthe weight of the load located therein.

DRIVE MECHANISM For a general understanding of my improved mechanismrefer now to FIGS. 1 and 2. The oscillating and spinning drive mechanism20 is driven by a reversible prime mover which, in the preferred form,is a reversible electric motor 28 which also drives a pump 26 (FIG. 2)in the water circulation system of the washing machine. The oscillatingand spinning drive mechanism 20 can be analyzed as having rotating drivetrain 30 and an oscillating or agitate drive means 80.

SPIN DRIVE The rotating drive train 30, as shown in FIGS. 2, 3 and 4,includes a spin drive roller 32 which is made of a polyurethane sleevesurrounding and frictionally engaging a spindle 33 extending from thereversible motor 28. The spin drive roller 32 frictionally drives a spinidler roller 34 which frictionally drives a driven spin roller 36 whichis relatively rotatably mounted about the tub drive shaft 22.

The spin idler roller 34 is maintained in position by an idler rollerretraction device 40 best shown in FIGS. 4 and 9. The idler rollerretraction device 40 is similar to the roller retraction assemblydescribed in detail in the US. Pat. No. 3,287,942, issued to Brackman etal. on Nov. 29, I966. The idler roller retraction device 40 has aU-shaped bracket 42 having arms 44 and 46 held apart by a spacer sleeve48. Located between the arms 44 and 46 are a pair of pivot links 50 and52. A bushing 54 is located between and rotatably mounted by the pivotlinks 50 and 52. The bushing 54 is located concentrically with respectto the spacer sleeve 48 and has an internal diameter larger than theexternal diameter of the spacer sleeve so that the bushing 54 may moveradially with respect to the spacer 48. An aluminum cast die insert 56is press fit on the bushing 54. A polyurethane tire 58 is molded on thealuminum insert 56 so that the bushing 54, the insert 56, and the tire58 form as a unit the spin idler roller 34.

An improved biasing arrangement comprises a part of my roller retractiondevice. Tabs 60 and 62 are formed in the U- shaped bracket support arms44 and 46, respectively. Mounted on the tabs 60 and 62 are two smallcoil springs 64 and 66. The springs 64 and 66 also seat respectively inholes 68 and 70 formed in the pivot links 50 and 52, respectively. Thetwo small coil springs bias the pivot links and bushing 54 away from thebase of the U-shaped bracket 42. The idler roller retraction device ismounted on the washing machine support plate 6 by a bolt 72 extendingthrough the spacer 48. A tab 74 extends outwardly from the bracketsupport arm 44 and is inserted in a hole located in the support plate 6to limit the pivoting of the U-shaped bracket 42 around the bolt 72.

The idler roller retraction device 40 with the spin idler roller 34 ismounted so as to locate the spin idler roller 34 between the spin driveroller 32 and the driven spin roller 36 in a self-energizing manner asshown in FIG. 3 and earlier taught in my US. Pat. No. 3,087,321. Thesprings 64 and 66 bias the spin idler roller 34 into engagement with therollers 32 and 36.

When the spin drive roller 32 is driven counterclockwise (FIG. 3) thespin idler roller 34 will be driven clockwise. The frictional forcesbetween the roller 32 and 34 along with the biasing forces of thesprings 64 and 66 will help draw the spin idler roller 34 intoengagement with the spin drive roller 32 and the driven spin roller 36.The driven spin roller 36, now being driven in a counterclockwisedirection, will impart this motion to the spin tub 16 through the tubdrive shaft 22 and a clutch 136 to be described hereinafter.

However, when the direction of rotation of the spin drive roller 32 isreversed, the frictional forces between the roller 32 and the spin idlerroller 34 will work against the springs 64 and 66 so as to push theidler spin roller 34 toward the base of the U-shaped bracket 42, andthus reduce the frictional forces between rollers 34 and 36 in therotating drive train 30. Thus, the idler roller retraction device 40accomplishes its purpose of increasing the frictional driving forces ofthe rotating drive means 30 during the spin operation of the washingmachine, and to reduce a rubbing or scuffing action between the spinrollers during an oscillating or washing action of the washing machinewhich is described in detail below.

AGITATE DRIVE The oscillating drive train 80 is best shown in FIGS. 2,3, 4 and 7. The reversible motor 28 directly drives an oscillator drivepulley 82 which is part of spindle 33. The first intermediate pulley 86is driven by the oscillator drive pulley through a first belt 84.Extending from the first intermediate pulley 86 is a second intermediatepulley 88 which drives another rotating member or driven oscillatorpulley 92 by means ofa second belt 90. This pulley drive system providesa speed reduction between the motor and the driven oscillator pulley.Extending downwardly from the driven oscillator pulley is a slidercrankpin 94. An elongated member or slider crank arm 96 is rotatablymounted at one end on the slider crankpin 94. A flexible slider crankmember or band 98 is connected to the slider crank arm 96 at both ends.The flexible slider crank member 98 forms a continuous bond in thatthere are no joints throughout its length and it extends or wraps aroundthe outer periphery of a slider crank drum 100 as best shown in FIGS. 3and 4.

The flexible slider crank member is formed of a material havingsufficient flexibility so as to wrap and unwrap repeatedly around theslider crank drum throughout an extended appliance life expectancy of 15years and having limited stretch characteristics. Several materials haveproven satisfactory for the flexible slider crank member, namely,stainless steel in several forms such as bands, or cables in variousarrangements. However, in the preferred form, the flexible slider crankmember comprises two pairs of continuous flexible cable members 102 and104. The cables are of multistranded (19 filament) steel wires twistedtogether and then covered with a plastic polyamide coating as shown inFIG. 5. The first pair of cables 102 is located slightly above thesecond pair of cables 104 and is joined to the slider crank arm 96 at anadjustable connection or cable tensioner 106. The first pair of cables102 partially extends around the slider crank drum 100 and isjoined tothe drum 100 by a cable key which fits in a drum indentation 108, (FIG.8). The lower or second pair of cables 104 is joined to the slider crankarm at the end opposite the adjustable connection 110 and also extendspartially around the slider crank drum 64 so as to also be joined to thedrum 100 by the cable key 110 at the drum indentation 108.

CABLE TENSIONER The flexible slider crank member is fastened to theslider crank arm 96 by an automatic cable-tensioning device as bestshown in FIG. 8. The slider crank arm 96 is rotatably secured to thedriven oscillator pulley 92 by the slider crankpin 94. At the end of theslider crank arm 96 furthest from the slider crankpin 94 is a slidercrank arm extension 114 having a notch 116. Located toward the slidercrankpin end of the slider crank arm 96 is a section extension orprojection 118. The extension 118 has a surface 120 which is slanted ata slight angle away from the pin 94. The two pair of cables 102 and 104are each embedded at one end thereof in the cable key 110 which in turnfits into the drum indentation 108. The free ends of the second pair ofcables 104 are embedded in a cable end piece 121 which in turn isriveted to a flat connector piece 122 having an opening 124. Similarly,the free ends of the first pair of cables 102 are embedded in a cableend piece 125 which in turn is riveted to a connector piece 126 havingan opening 128. The second pair of cables 104 is wrapped partiallyaround the drum 100 from the cable key 110 and the connector piece 122is slid over the end of extension 114 so that the opening 124 may catchin notch 116. The first pair of cables 102 is wrapped from the cable key1 10 around the slider crank drum 100 in a direction opposite that ofthe second pair of cables 104. The free end of the first pair of cables102 having the connector piece 126 is then positioned so that theopening 128 engages the slanted surface 120 of the slider crank armextension 118. Note from FIG. 8 that as the connector piece 126 ispushed on the sla'nted surface toward the base of the extension 118,greater tension is put on the cables 102, thus tightening the pair ofcables 102 and 104 around the slider crank drum 100. A spring 130 ispositioned in a hole 132 of the slider crank arm 96. The free end ofspring 130 is pulled upwardly against a spring pin 134 extending throughthe slider crank arm 96 so that the free end of the spring 130 engagesthe connector piece 126 of the first pair of cables 102 so as to biasthe connector 126 in a cable-tensioning direction on the slanted surface120. This adjustable connection provides an automatic tensioning on thecables and at the same time provides an automatic adjustment for anywear occurring in the slider crank mechanism. Furthermore, this tension,along with the wrapping of the cables around the slider crank drum,holds the cable key 110 in the drum indentation 108. When it is desiredto remove the cables, the connector piece 126 is released from spring130 and the cable key 110 drops out of the drum indentation 108 so thatthe whole cable assembly can be removed from the drum and slider crankarm.

AGITATE DRIVE OPERATION As the driven oscillator pulley 92 rotates, theslider crank arm 96 will move through a series of phantom positions 96,96', 96 and 96" as shown in FIG. 3 due to the pivotal connection withslider crankpin 94 and the engagement of the flexible slider crankmember 98 with the slider crank drum 100. It is readily seen that, asthe slider crank arm 96 is moved, the flexible slider crank member 98will reciprocate tangentially with respect to the slider crank drum 100.Since the flexible slider crank member 98 wraps around slider crank drum100 and since the flexible slider crank member both fixedly andfrictionally engages the slider crank drum 100, the reciprocatingtangential motion of the flexible slider crank member 98 will impart anoscillatory motion to the slider crank drum 100. Regardless of thedirection of rotation of the driven oscillator pulley 92, the slidercrank arm 96 and flexible slider crank member 98 will reciprocatetangentially with respect to the slider crank drum 100 and thus createthe oscillatory motion.

As shown in FIGS. 5 and 8, the slider crank drum 100 is positioned so asto oscillate around the tub drive shaft 22. In the preferred form, whilethe slider crank drum 100 is cylindrical in form, it is mounted slightlyoffset from the center of the tub drive shaft 22, thus giving aneccentric mounting for the slider crank drum 100 with respect to the tubdrive shaft 22. There is a slightly longer moment arm between the slidercrank arm and the tub drive shaft 22 when the slider crank arm 96 is atthe beginning and end of each stroke, which is when acceleration ishighest. Thus, when the slider crank arm is in positions 96 and 96", asshown in FIG. 3, the slider crank drum will be at a higher eccentricityand thus the speed of changing direction in the oscillation of theslider crank drum 100 is reduced. When the slider crank arm is inmidstroke, such as that shown in positions 96, and 96" in FIG. 3, whichis where acceleration is lowest and velocity is highest, the point oftangency of the flexible member 98 with the slider crank drum 100 is oflowest eccentricity with respect to the tub drive shaft 22-a pointdiametrically opposite the drum indentation 108. While the slider crankdrum need not be mounted offcenter with respect to the shaft 22, such amounting will provide reduced acceleration rates of the slider crankdrum when the slider crank drum is changing direction of oscillation.

In the preferred practice of this invention, there will be a speedreduction of approximately 25 to 1 between the oscillator drive pulley82 and driven oscillator pulley 92. Thus, a motor speed of 1,750 r.p.m.will give a driven oscillator pulley rotation of 70 r.p.m. The radialdistance between the center of the driven oscillator pulley 92 and thecenter of the slider crankpin 94 is approximately 3.14 inches, thusgiving a slider crank arm movement of 70 strokes a minute atapproximately 6.28 inches per stroke. With the slider crank drum 100having a radius of 1.466 inches offset approximately 0.20 inches fromthe center of the tub drive shaft, there will be an oscillation ofapproximately a 246 per stroke at 70 strokes a minute.

DRIVE CLUTCH AND OPERATION FIGS. 5 and 6 show a simplified clutch memberwhich is utilized in the preferred form of this invention. A driveclutch member or first portion of the clutch 136 is press fit on thelower portion of the tub drive shaft 22 and is further fastened to theshaft 22 by a bolt 138 so that any motion imparted to the clutch 136 isimparted to the tub drive shaft 22. The driven spin roller 36 includes aroller inner sleeve 156 which forms the second portion of the clutch.The inner sleeve 156 is located above the first portion 136 of theclutch and is biased downwardly by a coil spring 150 which seats againsta bearing 152. The driven spin roller 36 with the inner sleeve 156 canmove axially and rotate with respect to the shaft 22 to condition thefirst portion 136 of the clutch for either oscillation or rotation.Upward motion of the bearing 152 is prevented by a tub drive shaft pin154 and the bearing 152 through the spring 150 limits upward axialmotion of the driven spin roller 36. The clutch first portion 136 has atapered outer periphery 140. A sleeve bearing 142 is positioned aroundthe inner stem 1% of the clutch member 136. The slider crank drum whichis also the third portion of the clutch, rides on the bearing 142 andhas a tapered inner periphery 146. The sleeve bearing 142 has anoutwardly extending bearing flange 148 which provides a bearing surfacebetween the slider crank drum 100 and the driven spin roller 36.

The bottom surface of the inner sleeve 156 of the driven spin roller 36is provided with a cam surface having two vertical portions 160 and twohelical portions 162 as shown in FIG. 6. The inner upper surface of theclutch inner stern 144 is also provided with a clutch cam surface havingcomplementary vertical portions 164 and helical portions 166. When thedriven spin roller 36 is rotated in a clockwise direction, the camvertical portions 160 and 164 abut and the driven spin roller 36 withinner sleeve 156 may move axially with respect to the clutch member 136.The coil spring 150 can now bias the inner sleeve 156 of the driven spinroller 36 downwardly against the bearing flange 148 which, in turn,forces downwardly against the slider crank drum 100. When the slidercrank drum 100 is thus biased downwardly, the drum tapered innerperiphery 146 engages the clutch tapered outer periphery 140. The twotapered peripheries form a frustoconical friction clutch interface, and,thus, the oscillation motion of the slider crank drum 100 is imparted tothe clutch member 136. Since the clutch member 136 is press fit to thetub drive shaft 22, this oscillatory motion will be imparted to the spintub 16 and agitator 18 to provide an oscillatory agitating or washingmotion during the wash cycle of the washing machine. The bolt 138 isutilized to prevent any downward motion of the clutch member 136 and tohelp secure the press fit of the clutch member 136 to tub drive shaft22. The driven spin roller 36 oscillates with the clutch 136 andoverrides the lightly touching engagement of idler roller 34 in order toeffect a nondriving engagement.

When the reversible motor 28 is reversed for a spin operation, and thus,the driven spin roller 36 is rotated in a counterclockwise direction,the cam helical portions 162 and 166 will engage and thus bias the innersleeve 156 of the driven spin roller 36 upwardly against the coil spring150 since the clutch member 136 is fixed relative to the tub drive shaft22 and cannot move downwardly. As the coil spring 150 is compressed thedownward spring biasing force on the slider crank drum 100, through thesleeve bearing flange 148, is relieved and the normal force between thetapered peripheries and 146 is reduced to a point such that theoscillating slider crank drum 100 will slip relative to the clutch 1.36in order to effect a nondriving engagement. Thus, the oscillatory motionof the slider crank drum 100, which continues throughout the spin, willcease to be imparted to the clutch member 136 and the tub drive shaft22.

During this counterclockwise rotation of both the reversible motor 28and the driven spin roller 36, the spin idler roller 34 will beself-energized into a wedging or power transmitting engagement with thedriven spin roller 36 by the roller retraction device 40, as explainedabove. The upward motion of the driven spin roller 36 is limited by thebearing 152 and the tub drive shaft roll pin 154, shown in FIG. 5. Thislimiting of the upward motion of the driven spin roller 36 insures acontinuous engagement of the helical cam portions 162 and 166 when thedriven spin roller 36 is rotated in the counterclockwise direction asviewed in FIGS. 3 and 6. Therefore, the counterclockwise rotary motionof the driven spin roller 36 is imparted to the clutch member 136through the inner sleeve 156 and the helical cam portions 162 and 166.Since the spin idler roller 34 is in a-wedging or power-transmittingengagement with the driven spin roller 36 and since the slider crankdrum 100 may now slip with respect to the clutch member 136, thecounterclockwise rotary motion of the driven spin member 36 overridesany oscillatory motion of the slider crank drum 100 and thus a rotarymotion is imparted to the clutch member 136 and tub drive shaft 22. Thisprovides a rotary or spin motion for the spin tub and agitator l6.

DRIVEN SPIN ROLLER CLUTCH A secondary clutch 200 may be provided withinthe driven spin roller 36. The main purpose of this secondary clutch 200is to increase the life of the mechanism by providing another surfacewhere slippage can occur during the peak moments of acceleration anddeceleration or change of direction of drive of the agitate and spindrive mechanism 20. The secondary clutch includes a clutch plate 202extending radially from the spin roller inner stem 156 so that motionimparted to the clutch plate 202 is imparted to the inner stem and viceversa. A top clutch lining 21M and a bottom clutch lining 206 arepositioned parallel and adjacent the clutch plate 202. Each clutchlining 204 and 206 has an undulating peripheral edge which extends intothe complementarily undulating inner surface of the driven spin roller36 to form a rather splinelike connection therewith so that motion ofthe driven spin roller is imparted to the clutch linings and vice versa.The bottom clutch lining 206 rides on washer 208 which in turn ridesagainst the bottom cover 210 of the driven spin roller 36. Locateddirectly above the top clutch lining 204 is a clutch spring guide 212. Aclutch spring retainer 214 is located near the top of the inside of thedriven spin roller 36 and is positioned in one of a plurality ofinternal grooves 216. A clutch spring 218 is positioned between theclutch spring retainer 214 and the clutch spring guide 212 so as to biasthe clutch linings 204 and 206 into a tight sandwich against the clutchbrake 202. The plurality of internal grooves are provided so that theclutch spring retainer 214 may be adjusted vertically so as to vary thebiasing force of the clutch spring 218 and thus provide a method toadjust the point of slippage of the clutch inner spaces between theclutch linings 204 and 206 with the clutch plate 202.

Rotary motion of the driven spin roller 36 is imparted to the innersleeve 156 through the clutch linings 204 and 206 and the clutch plate202. Thus, a clockwise rotation of the driven spin roller 36 as shown inFIG. 6 will impart a clockwise rotation of the inner sleeve 156 so thatthe vertical cam portion 160 of the inner sleeve 156 can engage thevertical cam portion 166 of the clutch inner stem 144. At this time thespring 150 causes a downward motion of the inner sleeve 156 so as toforce the engagement of the slider crank drum 100 with the clutch 136 asdescribed above. When the driven spin roller 36 is rotated in acounterclockwise direction, this counterclockwise rotation will beimparted to the inner sleeve 156 again through the clutch linings 204and 206 and clutch plate 202. This causes the helical cam portions 162and 166 to engage so as to force the inner sleeve 156 upwardly againstspring 150 as described above. The compression of the spring 218 issufficient to eliminate slippage between the clutch linings and theclutch plate 202 during normal mode of operation of the drive mechanism.However, limited slippage may occur at the point when the mode ofoperation of the drive mechanism is changed if excessive torque might beapplied such as during a change from oscillation to spinning or viceversa or during braking. This reduces wear and tear on the mechanism andthus increases the life. it is thus seen that, except when excess torquemight be applied, the driven spin roller 36, the clutch 200 and theinner sleeve 1S6 act as a single unit and thus rotate together.

BRAKING The clutch 136 and slider crank drum 100 of this arrangementalso provide a unique braking system for the spin tub 16 (HO. 2). At theend of the spin cycle, the power to the reversible motor 28 is shut offcausing the motor to stop. The friction between the elements of therotating drive means 30 resists the rotation of the driven spin roller36. Similarly, the friction in the oscillating drive means resists theoscillation of the slider crank drum 100. However, even after the motor28 is shut off, the spin tub 16 continues to rotate due to the inertiaof the combined mass of the spin tub 16 and the clothes load locatedtherein. It is desirable to stop the rotation of the spin tub 16 asquickly as possible after the end of the spin cycle. Since the clutchmember 136 is joined to the single spin tub shaft 22, the clutch member136 also continues to rotate in a counterclockwise direction, as shownin FIG. 3. Since the clutch member 136 continues to rotate and thedriven spin roller 36 has stopped rotating, there is a relative rotationbetween the helical cam portion 162 of the driven spin roller and thehelical cam portion 166 of the clutch member (FlG. 6). This relativerotation causes the vertical cam surfaces 160 and 164 to again abut,again making possible axial movement of the driven spin roller 36 withrespect to the shaft 22. Since axial movement is possible, the coilspring 150 again biases the inner sleeve 156 and thus the driven spinroller 36 downwardly against the bearing flange 148. This downwardlybiasing force is then transmitted to the slider crank drum causing thedrum inner periphery 146 of the slider crank drum 100 to come intocontact with the outer tapered periphery of the clutch 136. The slidercrank drum 100 and the clutch 136 are now in the same relative positionas occurs during the oscillation drive except that now the slider crankdrum 100 is stationary and the clutch 136 is rotating. The rotary motionof the clutch 136 is now imparted to the stationary crank drum 100. Asthe slider crank drum 100 is rotated, a tangential linear motion isimparted to the slider crank arm 96 through the flexible slider crankmember 98. The motion of the slider crank arm 96 is imparted to thedriven oscillator pulley 92 against the friction of the oscillatingdrive means 80. Since the motion imparted to the slider crank drum 100by the clutch 136 is rotary and not oscillatory, the motion imparted tothe slider crank arm 96 is limited by the amount of rotation possible ofthe driven oscillator pulley 92.

Returning to FIG. 3, it is seen that as the spin tub overruns therotation imparted to the slider crank drum 100 is in a counterclockwisedirection of rotation. If the slider crank 96 is in the position 96',there is a rotary motion imparted to the driven oscillator pulley 92that will be in a counterclockwise direction. Similarly, if the slidercrank arm 96 is in the 96" position, the motion imparted to the drivenoscillator pulley 92 will be in the clockwise direction. However, oncethe slider crank arm 96 has reached the position 96", the forcedrotation of the driven oscillator pulley 92 will cause the slider crankarm 96 to move in a direction opposite the tangential linear force beingapplied by the counterclockwise rotation of the slider crank drum 100.Since the rotation of the slider crank drum 100 prevents the kickbackmotion of the slider crank arm 96, the slider crank arm 96 will stop inthe 96" position. This prevents the slider crank drum 100 from furtherrotation. Since the slider crank drum 100 is now again stationary, thereis relative slippage between the clutch 136 and the slider crank drum100 (FIG. 5). This slippage creates a frictional braking force on thisclutch 136 and thus a braking force on the shaft 22 and the spin tub 16.Due to the use of the slider crank drum 100 as a brake for the driveclutch 136, in the preferred form of this invention, the slider crankdrum 100 is made of a friction brake material. During the initialbraking action, part of the initial shock of the braking forces isabsorbed by the friction of the oscillating drive means 80 by way of thereaction imparted to the slider crank 96. The remainder of the brakingreaction force not absorbed, causes a rotation of the total suspendedmass in a counterclockwise direction as viewed in FIG. 3. Thiscounterclockwise direction rotation of the suspended mass is thenabsorbed by the springs of the suspension system (FIG. 1) so that thetotal shock or jerk of the braking reaction is not absorbed by theflexible slider crank member 98 in the preferred form of this invention.

BELT TENSIONER A belt tensioner assembly 170 (FIG. 7) is used in thepreferred form of this invention to provide the proper tension for thebelts utilized in the pulley driven system of the oscillating drivemeans 80. The driven oscillator pulley 92 is rotatably mounted on thesupport plate 6 by means of a bolt 172 and sleeve bearing 174.Thesupport plate 6 is also provided with an enlarged opening 176. Thebelt tensioner assembly 170 is provided with an angle bracket 178mounted below the enlarged opening 176. Located above the opening 176 isa washer 180 having a diameter larger than the internal diameter of theopening. A spacer washer 182 having a thickness slightly larger than thethickness of the support plate 6 is located between the angle bracket178 and the washer 180. The spacer washer 182 has an OD. smaller thanthe ID. of the enlarged opening 176. Positioned below the angle bracketis the combination first intermediate pulley 86 and second intermediatepulley 88 on the sleeve bearing 174. The bolt 172 is utilized to holdthe belt tensioner assembly 170 together and also mount the assembly onthe support plate 6. Since the spacer washer 182 is slightly thickerthan the support plate 6, and since the outer diameter of the spacerwasher 182 is smaller than the internal diameter of the opening 176, thebelt tensioner assembly 170 is relatively free to move radially withrespect to the center of the opening 176. The lower end of the anglebracket 178 has an opening 188. One hooked end of a coil spring 190 isinserted through the opening 188 while the other hooked end at the otherend of the spring is secured to a bracket 192. The coil spring 190biases the belt tensioner assembly 170 so as to provide a tension forboth the first belt 84 in the first intermediate pulley 86 and thesecond belt 90 in the second intermediate pulley 88. As noted before,the second belt 90 drives the driven oscillating pulley 92 while thefirst belt 84 is driven by the oscillator drive pulley 82. The coilspring 190 and thus the bracket 192 are located at an angle so as toprovide a tension of approximately pounds on the first belt 84 and 60pounds on the second belt 90 through the belt tensioner assembly 170.The assembly 170 is shown in FIG. 3 at a position which will giveapproximately the proper tensioning for the pulley system in theoscillator drive means 80.

It should, therefore, be seen that an improved oscillating and spinningmechanism has been devised including a single shaft drive system for alightweight combination spin tub and agitator. This simplified drivesystem eliminates the need for an oil bath lubrication system and isprovided with tensioning systems so as to keep the drive mechanism inproper adjustment. The drive mechanism also utilizes a simplified clutchmechanism which imparts either an oscillatory washing motion or a rotaryspin motion dependent upon the direction of rotation of a drive motor.The present invention provides a simplified drive mechanism for a washerwhich is easily manufactured, relatively inexpensive, light in weight,and having good life characteristics due to a combination ofself-adjustment features utilizing less critical manufacturingtolerances than those found in other washing machine drive mechanisms.

While the embodiments of the present invention as herein disclosedconstitute the preferred forms, it is to be understood that other formsmight be adopted.

lclaim:

1. In combination, a washing machine having a lightweight unitary spintub and agitator, and a drive mechanism to selectively oscillate androtate said spin tub and agitator, said drive mechanism comprising; asingle shaft: means, a tub support located at one end of said singleshaft means, said tub support extending into and covered by the agitatorportion of said spin tub and agitator, a reversible motor rotatable fordriving said shaft means, support means for said motor and said shaftmeans, clutch means at the other end of said shaft means for selectivelyoscillating and rotating said shaft means, rotatable means driven bysaid reversible motor and rotatably mounted with respect to said shaftmeans, said rotatable means axially movable with respect to said shaftmeans to selectively condition said clutch means for oscillation orrotation, a slider crank mechanism driven by said reversible motor,oscillatable means oscillated by said slider crank mechanism uponrotation of said motor in either direction, said oscillatable meansbeing located with respect to said clutch means so as to engage saidclutch means when said rotatable means conditions said clutch means foroscillation by rotation of said motor in a first direction, and saidclutch means upon rotation of said motor in an opposite direction beingcondition for rotation by axial movement of said rotatable means andbeing clrivingly rotated by said rotatable means, whereby the motion ofsaid clutch means is imparted to said unitary spin tub and agitatorthrough said single shaft means.

1. In combination, a washing machine having a lightweight unitary spintub and agitator, and a drive mechanism to selectively oscillate androtate said spin tub and agitator, said drive mechanism comprising; asingle shaft means, a tub support located at one end of said singleshaft means, said tub support extending into and covered by the agitatorportion of said spin tub and agitator, a reversible motor rotatable fordriving said shaft means, support means for said motor and said shaftmeans, clutch means at the other end of said shaft means for selectivelyoscillating and rotating said shaft means, rotatable means driven bysaid reversible motor and rotatably mounted with respect to said shaftmeans, said rotatable means axially movable with respect to said shaftmeans to selectively condition said clutch means for oscillation orrotation, a slider crank mechanism driven by said reversible motor,oscillatable means oscillated by said slider crank mechanism uponrotation of said motor in either direction, said oscillatable meansbeing located with respect to said clutch means so as to engage saidclutch means when said rotatable means conditions said clutch means foroscillation by rotation of said motor in a first direction, and saidclutch means upon rotation of said motor in an opposite direction beingcondition for rotation by axial movement of said rotatable means andbeing drivingly rotated by said rotatable means, whereby the motion ofsaid clutch means is imparted to said unitary spin tub and agitatorthrough said single shaft means.